S Maskani - Master of Midwifery, Dr. Ghani Health Center, Sabzevar, Iran.
M Tafazoli - Instructor, Faculty member of Midwifery Department, School of Nursing and Midwifery, Mashhad University of Medical Sciences, Mashhad, Iran
H Rakhshandeh - Pharmacological Research Center of Medicinal Plants, Mashhad University of Medical Sciences, Mashhad, Iran
H Esmaily - Ph.D. in Biostatistics, Social Determinants of Health Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

Background: Premenstrual syndrome is a collection of emotional, behavioral, and physical symptoms. This syndrome reduces the quality of life. Quality of life is a major measure in medical and health care. The aim of this study was to determine the effect of Nigella sativa seeds capsules on the quality of life of students with premenstrual syndrome.Methods: Double blind randomized clinical trial study was performed on 84 students with symptoms of premenstrual syndrome residing in girls dormitories in Mashhad University of Medical Sciences in 1396. The subjects were randomly divided into intervention and control groups. The intervention group received 1500 mg of Nigella sativa seeds Capsule daily from 7 days before the onset of menstrual bleeding to the first 3 days of menstrual bleeding for 2 cycles, and the placebo group received similar capsules containing the same ratio of lactose and starch in the same conditions. Quality of life and severity of symptoms were compared to the end of the second month of interventiontwo with before intervention. Data were analyzed by SPSS version 23 and Mann-Whitney, Wilcoxon, Independent T-test and paired T-test. The significance level was considered as P <0.05.Results: In this study, the quality of life of students with premenstrual syndrome was significantly higher in the intervention group than in the control group, at the end of the second month of taking the Nigella sativa seeds Capsule (P<0/001). Conclusion: The Nigella sativa seeds Capsule is effective in improving the quality of life of students with premenstrual syndrome

Nigella sativa, Premenstrual Syndrome, Quality of life.